@herjen Ideally you should save this gist as an html file, then place it in the same directory as the file you want to test. Then, for each iframe, change the "src" attribute to the name of the file you want to test. Then, load this file in your browser.

Hi @lensco do you mind if I take this gist, modify it, make it a git repo and push it to my GitHub account? I would link to your original gist and blog post in the readme. I'd like to avoid any copyright issues so I thought I'd ask first.